JPS6253188A - Dc motor controller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a wiper DC motor having a first armature brush that is grounded and a second armature brush that is connected to a terminal by a battery.

In other parts of this specification, "terminal" is used to refer to the armature brushes of a motor.

A DC motor control device according to the present invention includes a manual switch and a system for controlling the motor stop to a fixed position corresponding to a wiper stop position, and the system includes at least one line having a conductive sector and an insulating sector. an electrical circuit having at least one sliding contact piece adapted to interact with the rail so that a relative rotational movement controlled by the electric motor occurs between the sliding contact piece and the rail; One of the elements formed by the sliding contact piece or said track is connected to the supply terminal of the armature of said motor, while the other element (rail or sliding contact piece) can be grounded during said relative rotational movement. In this combination, the power supply to the electric motor is maintained until a desired fixed stop position by the interaction of the one or more rails and one or more sliding contact pieces. When this position is reached, the power supply to the electric motor is cut off and the armature of the electric motor is short-circuited.

Such a control device is particularly satisfactory with regard to its service life and the accuracy with which it achieves a constant stopping position.

However, such devices could cause interference with radio transmitters or receivers. Furthermore, in this type of device, if the wiper is accidentally moved and the manual switch is in the stop position, the wiper motor is driven without the user's intention.

It is a particular object of the present invention to create a control device for a DC wiper motor as described above, which satisfies various practical requirements in a better manner than hitherto, and which, in particular, no longer involves the above-mentioned disturbances or eliminates them. We are trying to make this even smaller.

According to the present invention, the above-mentioned DC wiper motor control device has the above-mentioned element (sliding contact piece or rail) that remains open when the wiper motor is operating normally and presses the manual switch. The electric motor is characterized in that it is connected to a power supply terminal of the electric motor by means of a breaker means which is closed when the electric motor is driven and the stop of the electric motor is controlled.

Generally, the power supply terminal of an electric motor is a positive terminal. It is best to make the rails rotary.

Electric circuits with sliding contacts, as is well known, have six sliding contacts, of which the first contact is grounded and the second contact is used to supply power to the motor. The third contact piece forms an element connected to the terminal, and the third contact piece is connected to the terminal which is connected to the second terminal of the armature of the motor when the manual control switch is set to the stop position. The armature is short-circuited at a fixed rest position between the first and third sliding contact pieces.

In the first case, the electric breaker means comprises a relay, the winding of which is connected to each terminal of the motor when driving a manual switch and controlling the stopping of the motor, while the said element to the supply terminal of the motor The connection (sliding contact piece or rail) is made by the actuating contact piece of this relay. When the manual switch is actuated to stop the motor, the relay is energized and the actuating contacts close in response to the voltage supplied by the motor, in this case acting as a generator.

When the device comprises six sliding contact pieces, the relay winding is connected between the first sliding contact piece and the third sliding contact piece, while the second sliding contact piece is activated as described above. It is connected to the power supply terminal of the electric motor by means of a contact piece.

According to the invention, the breaker means comprises a semiconductor element (especially a thyristor or a transistor). The transition of this element into the conductive state is controlled by the voltage present at each terminal of the motor, which acts as a generator at the instant of stopping.

When this breaker consists of a thyristor or similar,
The gate of this thyristor is connected to the motor terminals by a resistor having an appropriate value when the switch is set to the stop position.

For systems with 6 sliding contacts, the '7'-gate of this thyristor is connected to the third terminal connected to the motor terminals.
Connect to the sliding contact piece. According to the invention, the manual control switch also includes the aforementioned elements (sliding contacts or rails) only in the manual switch position corresponding to stopping the motor.
and the positive feed terminal of the motor, while in the other position of the switch the electrical connection between said element and the feed terminal is interrupted.

A diode can be connected to each terminal of the relay to prevent reverse current.

The breaker means provided between the aforementioned elements and the supply terminals can be located on or within the housing of the motor.

Embodiments of a DC motor control device according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 illustrates a control device for a DC motor (hereinafter simply referred to as a motor) 1 for a windshield wiper (not shown). Electric motor 1 is equipped with an armature. A first terminal a of this armature is grounded, and a second terminal a is connected to a power supply terminal 2 constituting the positive terminal. In this example, the electric motor 1 is capable of driving the wiper at two different speeds. For this purpose, electric motor 1
has an armature winding which is grounded at one end and terminates in the terminals described above which are angularly offset with respect to terminal C at the other end. These two terminals are connected to the power supply terminal 2. When a positive supply voltage is applied to the terminals, the wiper motor 1 and thus the wiper operate at a low speed. When terminal C is connected to terminal 2, motor 1 and thus the wiper operate at high speed.

As shown diagrammatically in FIG. 1, the terminals are connected by conductive wires to a manual switch 9 having a contact piece 3 in the form of an elongated rectangle. The other terminal C is connected to another roughly square contact piece 4 by a conductive wire. The contact piece 4 is arranged in an extension of the contact piece 3 but is separated from it by an insulating strip 5.

The terminal 2 is arranged parallel to each contact piece 3, 4 and is connected by a conductive wire to a contact piece 6 separated from the contact piece 3, 4 in a direction perpendicular to the length of the contact piece 3. A contact piece 7, which has the same shape as the contact piece 4, is arranged in an extension of the contact piece 6, but is separated from it by an insulating strip 8. The smaller lateral edges of the set of contact pieces 3, 4 and the set of contact pieces 6, 7 are aligned in a direction perpendicular to the length of each contact piece 3, 6. The width of strip 8 is equal to the width of strip 5.

The manual switch 9 includes a generatrix 10 located in a direction perpendicular to the lengths of the contact pieces 3 and 6. The dimensions of the generatrix 10 are approximately equal to the distance between the axes of each contact piece 3,6. That is, the bus bar 10 electrically connects one contact piece of the set of contact pieces 3 and 4 to another contact piece of the set of contact pieces 6 and 7 according to the position of the bus bar 10. Movement of the bus bar 10 is controlled by a handle 11 mechanically connected to the bus bar 10 and electrically insulated from the bus bar 10.
Control from.

In the first position of the handle 11, which corresponds to the position of the bus bar 10 indicated by the solid line in FIG. Ru.

In the second position of the bus bar 10, indicated by the dashed line, which corresponds to a slight movement to the right in FIG. 1, the bus bar 10 makes an electrical connection between the contact pieces 3, 6. In this case, the terminal is connected to the power supply terminal 2.

Finally, at the third position of the bus bar 10, which is further moved to the right in FIG. 1 and indicated by a broken line, the contact pieces 4 and 6 are electrically connected. In this case, terminal C is connected to power supply terminal 2.

The control device of the present invention is made to cooperate with a system S that controls stopping of the electric motor 1 to a fixed position corresponding to the stop position of the wiper.

The system S consists of three sliding contact pieces 12 that interact with rotating concentric circular tracks provided on the connector 15;
It is equipped with an electrical circuit with 13.14. Connector 15
consists of a generally circular conductive metal annular body rotated around its center 16 by a coupling mechanism (not shown) from the electric motor 1. During this rotation of the electric motor 1, the three sliding contact pieces 12, 13, 14 are connected to the connector 15 at 6
The strips move along mutually concentric circular tracks. The innermost circular track is provided with an insulating sector 1γ formed by a notch K provided at the inner edge of the annular connector 15. The outermost track comprises as electrically conductive elements only sectors 18 which project radially with respect to the external contour of the connector 15. Each sector 17,18 has the same bisecting radius, but the opening angle of sector 17 is greater than the opening angle of sector 18. The first sliding contact piece 12 corresponds to an outer track formed by a conductive sector 18 with a small angular extent and an insulating sector extending over the remainder of the circumference. The second sliding contact piece 13 rests on an inner track consisting of an insulating sector 17 and a conductive sector extending over the remainder of the circumference.

The third sliding contact piece 14 corresponds to a central rail that is electrically conductive over its entire circumference.

The first sliding contact piece 12 is grounded.

The second sliding contact piece 13 is connected to the power supply terminal 2 (positive terminal) by a breaker means I. The breaker means I remains open when the wiper electric motor 1 is operating normally (at low speed or high speed), but when the manual switch 9 controls the stop of the electric motor 1, i.e. when the bus bar 10 is closed. When placed in the position indicated by the solid line in FIG. 1, it is closed.

According to the structure shown in Figure 1, the breaker means is relay 1.
It has 9. A winding 20 of the relay 19 is connected to each terminal of the motor 1 between a first sliding contact piece 12 (ie ground) and a third sliding contact piece 14. The second sliding contact piece 13 is connected to the terminal 2 (positive terminal) by the actuating contact piece 21 of the relay 19 . The actuation contact 21 closes when the relay 19 is energized, ie when the winding 20 is energized. Contact piece 21 opens when relay 19 is deenergized.

Further, the third sliding contact piece 14 is electrically connected to the contact piece 7.

Diode 22 is connected to each terminal of relay 19 to prevent reverse current. The anode of the diode 22 is grounded, while its cathode is connected to a relay terminal connected to the sliding contact piece 14.

Under these conditions, the operating mode of this device is the following energization.

The starting point of the device is a stop position as shown in FIG.

Operate the switch 9 and move it to the operating position corresponding to low speed, for example. Under these conditions, the generatrix 10 is moved to the right into the first position indicated by the dashed line and the contact piece 6 is moved to the right.
and the contact piece 3 are electrically connected. In this case, the terminal of the motor 1 is connected to the positive power supply terminal and the motor 1 starts rotating at a low speed driving the wiper and the connector 15.

The relay 19 is not energized because the terminal connected to its sliding contact piece 14 is isolated from the positive power supply terminal 2 and from the terminals. The actuating contact 21 remains open and the sliding contact 13 receives no supply voltage.

Under these conditions, during the rotation of the connector 150, the sliding contacts 13, 14 are electrically connected by the annular connector 15. When the end occurs at an angular position of the connector 15 outside the insulating sector 17], the sliding contact piece 14 does not reach the voltage of the positive terminal but remains approximately at ground potential.

When sliding contact piece 14 and sliding contact piece 12 are electrically connected to each other, this condition occurs when the end of sliding contact piece 12 contacts sector 18, as shown in FIG.
The sliding contact piece 14 remains at the earth potential.

That is, during normal operation, the sliding contact piece 14 is not subjected to potential fluctuations between the positive potential of the power supply terminal 2 and the ground potential. Therefore, no voltage transition occurs at the contact piece 14 or the connector 15. This voltage transition protects the entire environment by radiation. The rail system formed by the connecting conductors and the connector 15 has a stray capacity (5tray capacity). This stray capacitance is alternately charged and discharged when such voltage transitions occur and conducts substantial current during charging and discharging of this stray capacitance. The interference resulting from such development protects the electromagnetic environment.

Such voltage transitions of the sliding contact piece 14 and the connector 15 occur when the sliding contact piece 13 is directly connected to the terminal 2 without using the breaker means (1) according to the invention. The breaker means I can effectively suppress interference in the control device.

To stop the electric motor 1, the switch 9 is activated to bring the bus bar 10 to the position shown by the solid line in FIG. 1, and to electrically connect the contact piece 3 and the contact piece 7. The winding 20 of the relay 19 is
Motor 1 armature terminal.

Connected to a (low speed).

At the moment when this connection is made, the rotating connector 1
5 is an arbitrary position, and <K occupies a position where the sliding contact pieces 12 and 14 are not connected by the sector 18.

The motor 1, which is no longer supplied with current, continues to rotate due to its inertia and acts as a generator so as to maintain a positive voltage at the terminals. This voltage is applied to the terminals of the winding 20 of the relay 19 that is energized.

In this way, the actuating contact piece 21 is closed, and the sliding contact piece 13 is therefore connected to the power supply terminal 2. Sliding contact piece 13
With the connection thus made between and terminal 2,
The terminals of the motor 1 are again powered by the terminals 2 when the connector 15 assumes an angular position such that the sliding contacts 13,14 are electrically connected by the connector 15. This is what happens when the electric motor 1 does not occupy an angular position corresponding to a fixed stop position.

The motor 1 therefore remains energized until the end of the sliding contact piece 13 reaches the insulating sector 17, which corresponds to a certain stop position. At the same time, the sliding contact 12 is electrically connected to the sector 18 and the armature of the motor 1 is short-circuited due to the electrical connection that occurs between the sliding contacts 12.14. The electric motor 1 stops at this fixed stop position practically instantaneously.

Relay 19 is no longer energized and actuating contact 21 opens.

The control device according to the invention has the following additional advantages which are quite different from interference suppression. If the wiper is driven from the electric motor via a reduction gear, this reduction gear has some reversibility, especially if it has a high efficiency.

This reversibility allows the wiper to be manually moved to rotate the shaft of the motor 1 and the conductive connector 15 even when the motor 1 is stopped and the switch 9 is in the off position. Such movements occur at random times.

If the shaft of the motor 1 and therefore the connector 15 are moved several degrees by an amount sufficient to bring the sliding contact piece 13 into contact with the connector 15 when the breaker means I is not provided, the terminal of the motor 1 will slide against the sliding contact piece 14. It is connected to the power supply terminal 2 by the contact piece 13 and the direct connection between the sliding contact piece 13 and the terminal 2 . In this case, the electric motor 1 makes one revolution until it returns to its fixed rest position. This phenomenon will continue unless the cause of the wiper moving away from its rest position is removed.

This drawback can be eliminated by the breaker device according to the invention, since the contact piece 21 of the relay 19 is open at a certain stop position of the motor 1. Rotate the connector 15 several degrees from this fixed stop position and slide the sliding contact piece 14
Even if the sliding contact pieces 13 are connected to each other, the sliding contact piece 13 is isolated from the power supply terminal 2 because the contact piece 21 is open, so power cannot be supplied to the electric motor 1 through the sliding contact piece 13.

The electric motor 1 can only be started by activating the switch 9.

FIG. 2 shows a modification of the invention in which the electric breaker means (1) is provided with an additional thyristor 23 in place of the relay. The anode of the thyristor 23 is connected to the power supply terminal 2. The cathode of the thyristor 23 is connected to the sliding contact piece 13. The gate of thyristor 23 is connected to sliding contact piece 14 by a resistor 24 of suitable value. A capacitor 25 can be connected between this gate and ground.

In order to prevent potential fluctuations from causing interference during operation of the annular connector 15, a resistor 26 can be connected between the sliding contact piece 14 and the earth in FIGS. 1 and 2. .

The mode of operation of the device shown in FIG. 2 is similar to that described with respect to FIG. During normal operation of the electric motor 1, the thyristor 23 is non-conducting. When the switch 9 is set to the off position, the busbar 10 occupies the position represented by the solid line in FIG. The voltage applied to the terminal causes the thyristor 23 to drip, making it conductive. The motor 1 is again supplied with power from the terminal 2.

When the electric motor 1 reaches a certain stop position, the contact piece 13
is multiplied by the insulating sector 17, and the current passing through the thyristor 23 is cut off. Thyristor 23 becomes non-conducting again.

In addition, according to the present invention, the breaker means is such that the power supply voltage at the terminal 2 is increased only when the bus bar 10 occupies the position where the contact pieces 3 and 7 are connected to each other (the position of the bus bar 10 indicated by a solid line in FIG. 1). A switch 9 configured to apply a voltage to the sliding contact piece 14 is provided.

This embodiment has a system with six fixed sliding contact pieces and a rotating track. However, if the present invention is
As described in R-A-2,428,344, systems having different numbers of sliding contact pieces and/or tracks, each sliding contact piece being rotationally driven, each Obviously, the rails can also be applied to fixed systems.

Although the present invention has been described in detail with reference to its embodiments, it is obvious that the present invention can be modified in various ways without departing from its spirit.

[Brief explanation of drawings]

FIG. 1 shows one of the wiper DC motor control devices according to the present invention.
The electrical wiring diagram of the embodiment, FIG. 2 is an electrical wiring diagram of a modified version of the present control device. DESCRIPTION OF SYMBOLS 1... DC motor, 2... Power supply terminal, 9... Manual switch, S... System, 12,13.14...
Screw contact piece, 15... Connector (rail) FIG, 2 Procedural amendment (method) % formula %

Claims (11)

[Claims] (1) The first terminal of the armature is grounded and the second terminal of this armature
The terminal is equipped with a system and a manual switch for controlling the stop of the wiper DC motor connected to the power supply terminal to a fixed position corresponding to the stop position of the wiper, and the system includes a conductive sector and an insulating sector. at least 1 with
An electric circuit is provided having at least one sliding contact piece adapted to interact with the rail of the track, such that a relative rotational movement controlled by the electric motor occurs between said sliding contact piece and the rail. , one of the elements formed by the sliding contact piece or the rail is connected to a power supply terminal of the armature of the electric motor, while the other element (rail or sliding contact piece) is grounded during the relative rotational movement. is possible,
In this combination, the power supply to the electric motor is maintained until a desired fixed stop position by the interaction of the one or more rails and one or more sliding contact pieces. In the DC motor control device, the element (13) (sliding contact piece or rail) is connected to the wiper motor (1 ) remains open when it is operating normally and the manual switch (9)
The power supply terminal (
2) A DC motor control device characterized by being connected to. (2) A relay (19) is provided in the breaker means I, and the winding (20) of this relay is connected to the motor (1) when the manual switch (9) is driven to control the stop of the motor (1).
) and the element (13) (sliding contact piece or track) is connected to the actuating contact piece (21) of said relay.
is connected to the power supply terminal (2) of said electric motor and drives a manual switch (9) to control the stopping of said motor in response to the voltage supplied by said electric motor, in this case acting as a generator. The DC motor control device according to claim 1, wherein the relay (19) is energized to close the operating contact piece (21). (3) A semiconductor element (23) is provided in the breaker means I,
Claim (1) characterized in that the transition of this element to the conductive state is controlled by the voltage generated at terminals b and c of the electric motor (1) that acts as a generator during stop control. DC motor control device as described in . (4) A thyristor or similar is used as the semiconductor element (23), and the gate of this thyristor is connected to the motor terminal by means of a resistor (24) (of suitable value) when the switch (9) is set to the off position. 3. The DC motor control device according to claim 3, wherein the DC motor control device is connected to the DC motor control device. (5) The DC motor control device according to claim (4), characterized in that a capacitor (25) is connected between the gate of the thyristor (23) and ground. (6) An electric circuit having sliding contact pieces is provided with three sliding contact pieces (12), (13), (14), and among these contact pieces, the first contact piece (12) is grounded; The second contact piece (13) forms an element connected to the power supply terminal (2) of said electric motor, and the third contact piece (14) forms a manual control switch (
9) is connected to the terminal (7) which is connected to the second terminal b of the armature of the motor when set to the off position, and the armature is connected between the first and third sliding contact pieces. A DC motor control device according to any one of the preceding claims, characterized in that a short circuit occurs at a certain stop position. (7) The DC motor control device according to claim (6), characterized in that a resistor (26) is connected between the third sliding contact piece (14) and the ground. (8) Connect the winding (20) of the relay (19) between the first sliding contact piece (12) and the third sliding contact piece (14), and connect the second sliding contact piece (13). Claims (2) and (2) are characterized in that the actuating contact piece (21) is connected to the power supply terminal (2) of the electric motor.
The DC motor control device according to item 6). (9) Turn the gate of the thyristor (23) on the manual switch (
A third sliding contact piece (1
Claim No. 4) characterized in that it is connected to 4).
) and (6), or (5) and (6). (10) A manual control switch electrically connects the element (13) (sliding contact piece or rail) and the power supply terminal (2) of the motor starting from the position of the manual switch corresponding to the stoppage of the motor; However, in other positions of the switch, the electrical connection between the element (13) and the power supply terminal (2) is cut off. DC motor control device. (11) Any of the preceding claims characterized in that the breaker means I provided between the element (13) and the power supply terminal (2) is located on or within the housing of the motor (1). DC motor control device described in .